In mammals, injury triggers a complex cascade of cellular and biochemical events that result in a healed wound. Wound healing is a complex dynamic process that results in the restoration of anatomic continuity and function; an ideally healed wound is one in which the wounded tissue has returned to normal anatomic structure, function and appearance.
Certain factors, such as poor circulation and/or microbial contamination can delay or prevent the normal processes associated with wound healing. Early diagnosis of abnormal wound healing can permit a clinician to intervene with appropriate treatments (e.g., antibiotic therapy).
The status of a wound can be assessed by determining the presence and/or amount of certain analytes at the wound site. The analytes may be soluble analytes (e.g., total protein; enzymes, such as matrix metalloproteinase, plasmin, elastase, lactate dehydrogenase; and oxides of nitrogen, such as nitric oxide). The analytes may be certain types of cells (e.g., neutrophils, macrophages, fibroblasts).
Assessing a wound site typically involves the collection of sample material. Swabs are the most commonly-used device for collecting samples, but their efficacy is limited for certain analytical tests. Biopsies are used in certain situations, but they are invasive and can cause additional trauma to the wound site, further delaying the healing process. There is a need for a simple, noninvasive wound sampling method that is compatible with a plurality of analytical tests.